Description: ß-adrenergic receptors (ß-AR's) a class of G protein-coupled receptors that are targets of the catecholamines, especially noradrenaline (norepinephrine) and adrenaline (epinephrine). ß receptors have the subtypes ß1, ß2 and ß3. All three are linked to Gs proteins, which in turn are linked to adenylate cyclase. Agonist binding to these receptors therefore causes a rise in the intracellular concentration of the second messenger cAMP.

ß subtype1-adrenergic receptors (ß1-AR's) are expressed on a number of cell types, including cardiomyocytes, vascular smooth muscle, epithelium, renal juxtaglomerular, and adipocytes. These receptors are targets for agonists in the acute treatment of decompensated heart failure, while ß1-AR antagonists are utilized in the treatment of cardiovascular diseases such as chronic heart failure, ischemic heart disease, cardiac arrhythmias, and hypertension. However, the response to ß1-AR agonists or antagonists appears to be highly variable between individuals, which is not readily explained by clinical status or demographic characteristics. Furthermore, the inventor has previously shown that the expression of ß1-AR, and the responsiveness to stimulation, can differ substantially between healthy individuals. Such variability between individuals suggests that the receptor may be polymorphic in the population, giving rise to altered expression as well as altered physiologic or pharmacologic responsiveness.

Invention
Dr. Stephen Liggett at the University of Cincinnati has invented a method for determining whether a treatment protocol for a human patient who is suffering from heart failure, ischemic heart disease, cardiac arrhythmias, or hypertension would include the administration of a beta blocker. The method also involves identifying locations of any polymorphisms in the ß1-AR sequence from the patient's biological sample, assigning a haplotype to the ß1-AR sequence based on the locations identified, and determining whether the treatment protocol includes administration of a beta blocker to the patient based on the haplotype assigned.

The invention offers the following advantages:

the invention forms the basis of a test to determine the best treatment protocol for cardiovascular disease

treatment protocols can be potentially tailored around the patient's individual genotype. This could lead to savings in terms of both costs and time.

potentially lead to the avoidance of unnecessary side effects

A patent for this technology is pending. The published patent application can be found here